Heat sink for power module

ABSTRACT

A power module includes a power device and a heat sink. The heat sink includes a refrigerant passage in which a cooling medium flows and a corrugated fin body arranged in the refrigerant passage. The refrigerant passage is defined by a surface and a backside, and the power device is disposed in proximity to the surface. The corrugated fin body has crests and troughs that extend in the flow direction of the cooling medium and side walls each of which connects the corresponding one of the crests with the adjacent one of the troughs. Each adjacent pair of the side walls and the corresponding one of the crests or the corresponding one of the troughs arranged between the adjacent side walls form a fin. A guide that extends in the flow direction of the cooling medium and operates to stir the cooling medium is arranged in each of the fins.

TECHNICAL FIELD

The present invention relates to a heat sink for power module.

BACKGROUND ART

A conventional heat sink for power module is disclosed in, for example,Patent Document 1. The heat sink for power module is made of aluminum orcopper (the “aluminum” herein includes aluminum alloy other than purealuminum and the “copper” includes copper alloy other than pure copper).A refrigerant passage in which cooling medium such as water flows isdefined in the heat sink for power module. More specifically, the heatsink for power module has a laterally elongated rectangular crosssection. In the heat sink, the refrigerant passage having a laterallyelongated rectangular cross section is provided. Fins extending in anup-and-down direction are arranged in the refrigerant passage andincrease the contact area with respect to the cooling medium.

An insulated circuit substrate on which power devices such assemiconductor chips are mounted is arranged at one surface of the heatsink for power module. Before the power devices are mounted, thestructure is referred to as a substrate for power module including aheat sink for power module and an insulated circuit substrate.

The insulated circuit substrate includes, for example, a wiring layerformed of aluminum, an insulated substrate that is formed of insulatingceramic and joined to the wiring layer, and a heat radiating layer thatis formed of aluminum and joined to the insulated substrate. When thesubstrate for power module is used, power devices such as semiconductorchips are mounted on the wiring layer. A heat radiating plate that isformed of aluminum and sized at 3 to 10 mm is provided between theinsulated circuit substrate and the heat sink for power module.

The conventional heat sink for power module, which is configured asabove-described, forms a power module when an insulated circuitsubstrate on which power devices such as semiconductor chips are mountedis provided at one surface of the heat sink. The power module may beused in an inverter circuit of a movable body such as a hybrid vehicle,which employs an electric motor as one of its drive sources. In thiscase, the power module adjusts the power supplied to the electric motoror the like in correspondence with the operating state of the movablebody. The power module transmits intense heat generated by the powerdevices to the heat sink for power module through the wiring layer, theinsulated substrate, the heat radiating layer, and the heat radiatingplate. The heat is then dissipated by the cooling medium flowing in therefrigerant passage.

However, the conventional heat sink for power module has the followingproblem with regard to the efficiency of transmission of the intenseheat generated by the power devices to the cooling medium, which flowsin the refrigerant passage, from the refrigerant passage or the surfacesof the fins.

Specifically, in the above-described conventional heat sink for powermodule, the fins that extend in the up-and-down direction are providedin the refrigerant passage in order to increase the contact area withrespect to the cooling medium. However, regardless of the fins, thetemperature of the cooling medium becomes higher toward the areathermally closer to the power devices. The distribution of thetemperature of the cooling medium in the heat sink for power module thusbecomes nonuniform. This limits effective cooling performance of thecooling medium to a certain level and lowers the heat dissipatingefficiency. As a result, in the heat sink for power module, transmissionof the heat from the inner surfaces of the refrigerant passage or thesurfaces of the fins to the cooling medium is hampered. This makes itdifficult to further improve the heat dissipating performance.

-   Patent Document 1: Japanese Laid-Open Patent Publication No.    2003-86744

DISCLOSURE OF THE INVENTION

Accordingly, it is an objective of the present invention to provide aheat sink for power module that is capable of further improving heatdissipating performance.

In accordance with a first invention of the present application, thereis provided a heat sink for power module, the heat sink being capable ofmounting a power device on at least one surface of the heat sink. Theheat sink includes a refrigerant passage in which a cooling medium thatdissipates heat generated by the power device flows and a corrugated finbody arranged in the refrigerant passage. The corrugated fin body hascrests and troughs that extend in a flow direction of the cooling mediumand side walls each of which connects the corresponding one of thecrests with the adjacent one of the troughs. Each adjacent pair of theside walls and the corresponding one of the crests or the correspondingone of the troughs arranged between the adjacent side walls form a fin.Each of the side walls has a louver that operates to, at least, rotatethe cooling medium flowing in the associated fin. As long as the louverat least rotates the cooling medium, the louver may cause localturbulence. The body of the heat sink that defines the refrigerantpassage may be formed of aluminum or copper. The corrugated fin body mayalso be formed of aluminum or copper.

Japanese Laid-Open Patent Publication No. 2002-5591 discloses a heatsink for power module having a louver formed in a fin. However, the findoes not rotate the cooling medium but simply causes turbulence, whichmay lead to erosion. Contrastingly, the heat sink for power moduleaccording to the first invention rotates the cooling medium by means ofthe louver. This prevents erosion and improves the durability.

In the first invention, the corrugated fin body may form a rectangularwave shape. However, if the top surface of each crest and the bottomsurface of each trough are flat surfaces extending perpendicular to theside walls, the cooling medium is easily stopped at the portionscorresponding to the crests and the troughs. It is thus preferred thatthe top surface of each crest and the bottom surface of each trough becurved.

In accordance with a second invention of the present application, thereis provided a heat sink for power module, the heat sink being capable ofmounting a power device on at least one surface of the heat sink. Theheat sink includes

a refrigerant passage in which a cooling medium that dissipates heatgenerated by the power device flows and a corrugated fin body arrangedin the refrigerant passage. The corrugated fin body has crests andtroughs that extend in a flow direction of the cooling medium and sidewalls each of which connects the corresponding one of the crests withthe adjacent one of the troughs. Each adjacent pair of the side wallsand the corresponding one of the crests or the corresponding one of thetroughs arranged between the adjacent side walls form a fin. A guidethat extends in the flow direction of the cooling medium and operates tostir the cooling medium is arranged in each of the fins.

In the second invention, the body of the heat sink defining therefrigerant passage may be formed of aluminum or copper. The guide mayalso be formed of aluminum or copper. The guide may be formed by a wireor a belt-like member. Guides may be arranged in the fin. The guideaccording to the second invention extends in the flow direction of thecooling medium. In this regard, the concept of the guide is differentfrom that of an exchange device according to sixth invention, which willbe explained later.

To stir herein includes to rotate and to cause turbulence.

Also in the second invention, the corrugated fin body may form arectangular wave. However, if the top surface of each crest and thebottom surface of each trough are flat surfaces extending perpendicularto the side walls, the cooling medium is easily stopped at the portionscorresponding to the crests and the troughs. It is thus preferred thatthe top surface of each crest and the bottom surface of each trough becurved.

In accordance with a third invention of the present application, thereis provided a heat sink for power module, the heat sink being capable ofmounting a power device on at least one surface of the heat sink. Theheat sink includes a refrigerant passage in which a cooling medium thatdissipates heat generated by the power device flows and a guide memberarranged in the refrigerant passage. The guide member has a first guideplate and a second guide plate. The first guide plate is formed by acorrugated fin body including crests and troughs that are alternatelyarranged, and side walls each of which connects the corresponding one ofthe crests with the adjacent one of the troughs. Each adjacent pair ofthe side walls and the corresponding one of the crests or thecorresponding one of the troughs arranged between the adjacent sidewalls form a first fin. The first fin operates to guide the coolingmedium in a direction inclined at a first angle with respect to a flowdirection of the cooling medium. The second guide plate is formed by acorrugated fin body including crests and troughs that are alternatelyarranged, and side walls each of which connects the corresponding one ofthe crests with the adjacent one of the troughs. Each adjacent pair ofthe side walls and the corresponding one of the crests or thecorresponding one of the troughs arranged between the adjacent sidewalls form a second fin. The second fin operates to guide the coolingmedium in a direction inclined at a second angle, which is differentfrom the first angle, with respect to the flow direction of the coolingmedium.

In the third invention, the body of the heat sink that defines therefrigerant passage may be formed of aluminum or copper. Also, thecorrugated fin body may be formed of aluminum or copper.

Also in the third invention, the corrugated fin body may form arectangular wave. However, if the top surface of each crest and thebottom surface of each trough are flat surfaces extending perpendicularto the side walls, the cooling medium is easily stopped at the portionscorresponding to the crests and the troughs. It is thus preferred thatthe top surface of each crest and the bottom surface of each trough becurved.

In accordance with a fourth invention of the present application, thereis provided a heat sink for power module, the heat sink being capable ofmounting a power device on at least one surface of the heat sink. Theheat sink includes a refrigerant passage in which a cooling medium thatdissipates heat generated by the power device flows and a comb toothmember arranged in the refrigerant passage. The comb tooth member has asubstrate extending parallel with the surface on which the power deviceis arranged and a plurality of upright walls that project from thesubstrate in a direction crossing the surface on which the power deviceis arranged. Each of the upright walls extends along a flow direction ofthe cooling medium in the refrigerant passage. Each upright wall has aguide portion that operates to stir the cooling medium flowing betweenthe upright wall and the adjacent one of the upright walls.

In the fourth invention, the body of the heat sink defining therefrigerant passage may be formed of aluminum or copper. The comb toothmember may also be formed of aluminum or copper.

In accordance with a fifth invention of the present application, thereis provided a heat sink for power module, the heat sink being capable ofmounting a power device on at least one surface of the heat sink. Theheat sink includes a laminated body including a plurality of passageplates that are joined together and a plurality of parallel grooves thatare arranged between each adjacent pair of the passage plates. Each ofthe grooves functions as a refrigerant passage in which a cooling mediumthat dissipates heat generated by the power device flows. Each of thepassage plates includes a guide portion operating to stir the coolingmedium flowing in the corresponding groove.

In the fifth invention, each passage plate may be formed of metal suchas aluminum or copper, or ceramic such as aluminum nitride.

In accordance with a sixth invention of the present application, thereis provided a heat sink for power module, the heat sink being capable ofmounting a power device on at least one surface of the heat sink. Theheat sink includes a refrigerant passage in which a cooling medium thatdissipates heat generated by the power device flows and an exchangedevice arranged in the refrigerant passage. The exchange device movesthe cooling medium from an area of the refrigerant passage close to thesurface on which the power device is provided to an area of therefrigerant passage far from the surface on which the power device isprovided, and from the area of the refrigerant passage far from thesurface on which the power device is provided to the area of therefrigerant passage close to the surface on which the power device isprovided.

The exchange device according to the sixth invention does notnecessarily have to extend in the flow direction of the cooling mediumor stir the cooling medium by causing a rotating flow or turbulence. Inthis regard, the concept of the exchange device is different from thatof the guide according to the second invention.

In the sixth invention, the body of the heat sink that defines therefrigerant passage may be formed of aluminum or copper. The stirringdevice may also be formed of aluminum or copper.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view schematically showing a corrugated fin bodyof a heat sink for power module according to a first embodiment.

FIG. 2 is a cross-sectional view schematically showing the heat sink forpower module according to the first embodiment.

FIG. 3 is a top view schematically showing a thin aluminum plate forforming the corrugated fin body of the heat sink for power moduleaccording to the first embodiment.

FIG. 4 is a perspective view schematically showing a corrugated fin bodyof a heat sink for power module according to a second embodiment.

FIG. 5 is a cross-sectional view schematically showing the heat sink forpower module according to the second embodiment.

FIG. 6 is a perspective view schematically showing a corrugated fin bodyof a heat sink for power module according to a third embodiment.

FIG. 7 is a cross-sectional view schematically showing the heat sink forpower module according to the third embodiment.

FIG. 8 is a perspective view schematically showing a corrugated fin bodyof a heat sink for power module according to a fourth embodiment.

FIG. 9 is a cross-sectional view schematically showing the heat sink forpower module according to the fourth embodiment.

FIG. 10 is a perspective view schematically showing a guide of a heatsink for power module according to a fifth embodiment.

FIG. 11 is a cross-sectional view schematically showing the heat sinkfor power module according to the fifth embodiment.

FIG. 12 is a perspective view schematically showing a guide of a heatsink for power module according to a sixth embodiment.

FIG. 13 is a cross-sectional view schematically showing the heat sinkfor power module according to the sixth embodiment.

FIG. 14 is a perspective view schematically showing a guide formingmember of a heat sink for power module according to a seventhembodiment.

FIG. 15 is a perspective view schematically showing a guide of the heatsink for power module according to the seventh embodiment.

FIG. 16 is a cross-sectional view schematically showing the heat sinkfor power module according to the seventh embodiment.

FIG. 17 is a perspective view schematically showing a first guide plateand a second guide plate of a heat sink for power module according to aneighth embodiment.

FIG. 18 is a cross-sectional view schematically showing the heat sinkfor power module according to the eighth embodiment.

FIG. 19 is a perspective view schematically showing a first guide plate,a second guide plate, and a partition wall of a heat sink for powermodule according to a ninth embodiment.

FIG. 20 is a cross-sectional view schematically showing the heat sinkfor power module according to the ninth embodiment.

FIG. 21 is a front view schematically showing a heat sink for powermodule according to a tenth embodiment.

FIG. 22 is a side view schematically showing the heat sink for powermodule according to the tenth embodiment.

FIG. 23 is a bottom view schematically showing the heat sink for powermodule according to the tenth embodiment.

FIG. 24 is a front view schematically showing a heat sink for powermodule according to an eleventh embodiment.

FIG. 25 is a side view schematically showing the heat sink for powermodule according to the eleventh embodiment.

FIG. 26 is a perspective view schematically showing an upright wall anda recess of a comb tooth member of the heat sink for power moduleaccording to the eleventh embodiment.

FIG. 27 is a front view schematically showing a heat sink for powermodule according to a twelfth embodiment.

FIG. 28 is a side view schematically showing the heat sink for powermodule according to the twelfth embodiment.

FIG. 29 is a perspective view schematically showing an upright wall anda recess of a comb tooth member of the heat sink for power moduleaccording to the twelfth embodiment.

FIG. 30 is a perspective view schematically showing an upright wall anda through hole of a comb tooth member of a heat sink for power moduleaccording to a thirteenth embodiment.

FIG. 31 is a perspective view schematically showing a heat sink forpower module according to a fourteenth embodiment.

FIG. 32 is a top view schematically showing a passage plate of the heatsink for power module according to the fourteenth embodiment.

FIG. 33 is a schematic cross-sectional view taken along line J-J of FIG.32.

FIG. 34 is a top view schematically showing a passage plate of a heatsink for power module according to a fifteenth embodiment.

FIG. 35 is a schematic cross-sectional view taken along line K-K of FIG.34.

FIG. 36 is a schematic cross-sectional view taken along line L-L of FIG.34.

FIG. 37 is a top view schematically showing a passage plate of a heatsink for power module according to a sixteenth embodiment.

FIG. 38 is a schematic cross-sectional view taken along line M-M of FIG.37.

FIG. 39 is a schematic cross-sectional view taken along line N-N of FIG.37.

FIG. 40 is a top view schematically showing a heat sink for power moduleaccording to a seventeenth embodiment.

FIG. 41 is a side view schematically showing the heat sink for powermodule according to the seventeenth embodiment.

FIG. 42 is a schematic cross-sectional view taken along line O-O of FIG.40.

FIG. 43 is an enlarged cross-sectional view showing a main portion ofthe heat sink for power module according to the seventeenth embodiment.

FIG. 44( a) is a set of three views (a front view, a plan view, and aside view) showing a first plate of the heat sink for power moduleaccording to the seventeenth embodiment.

FIG. 44( b) is a set of three views showing a second plate of the heatsink for power module according to the seventeenth embodiment.

FIG. 44( c) is a set of three views showing a laminated body of the heatsink for power module according to the seventeenth embodiment.

FIG. 45( a) is a side view showing the laminated body of the heat sinkfor power module according to the seventeenth embodiment.

FIG. 45( b) is a side view showing an exchange device obtained bycutting the laminated body of FIG. 45( a).

FIG. 46 is a perspective view schematically showing an exchange deviceof a heat sink for power module according to an eighteenth embodiment.

FIG. 47 is a perspective view schematically showing an exchange deviceof a heat sink for power module according to a nineteenth embodiment.

BEST MODE FOR CARRYING OUT THE INVENTION

First to nineteenth embodiments of first to sixth inventions of thepresent application will now be described with reference to the attacheddrawings. In each of the drawings, an upper side corresponds to asurface and a lower side corresponds to a backside.

First Embodiment

A first embodiment corresponds to the first invention.

Power devices 101 may be mounted on a surface of a heat sink 1 for powermodule according to the first embodiment, which is shown in FIG. 2. Theheat sink 1 has a refrigerant passage 1 d in which cooling medium fordissipating heat generated by the power devices 101 flows.

The refrigerant passage 1 d of the heat sink 1 for power module is aspace with a rectangular cross section surrounded by a surface 1 b, abackside 1 c, and side surfaces (not shown), which are provided atopposing sides. The cooling medium flows from the side closer to theviewer of FIG. 2 toward the side farther from the viewer of the drawing.

As shown in FIGS. 1 and 2, a corrugated fin body 1 a is arranged in therefrigerant passage 1 d. The corrugated fin body 1 a has crests 21 b andtroughs 21 c, which extend in the flow direction of the cooling medium,and side walls 21 a. The crests 21 b and the troughs 21 c arealternately provided in a direction perpendicular to the flow directionof the cooling medium. Each of the side walls 21 a connects thecorresponding one of the crests 21 b with the adjacent one of thetroughs 21 c. Each adjacent pair of the side walls 21 a and theassociated one of the crests 21 b, which is located between the sidewalls 21 a, form a fin 21.

Each of the side walls 21 a has louvers 31, which operate to, at least,rotate the cooling medium flowing in the associated one of the fins 21.The louvers 31 are formed simultaneously with the corrugated fin body 1a.

Specifically, the corrugated fin body 1 a is manufactured using a thinaluminum plate 90 shown in FIG. 3. The thin aluminum plate 90 hasbelt-like sections A that form the troughs 21 c after bending, belt-likesections B that extend parallel with the belt-like sections A and areform the crests 21 b after bending, and belt-like sections C that arearranged between the belt-like sections A and the belt-like sections Band extend parallel with the belt-like sections A and the belt-likesections B. Each of the belt-like sections C is formed in such a mannerthat cuts 31 a and bending lines 31 b are aligned in the direction inwhich the belt-like section C extends. Each of the cuts 31 a and theassociated one of the bending lines 31 b form an isosceles trapezoidwith the bending line 31 b serving as the bottom side. Each of theisosceles trapezoids formed by the cuts 31 a and the bending lines 31 bis inclined at a predetermined angle with respect to the alignmentdirection, or the extending direction of the belt-like sections C.

To form the louvers 31 in the thin aluminum plate 90, which isconfigured as above-described, the sections defined by the cuts 31 a arebent along the bending lines 31 b from the side farther from the viewerof FIG. 3 to the side closer to the viewer of the drawing. Subsequently,the thin aluminum plate 90 is bent in such a manner that the belt-likesections A form the troughs 21 c and the belt-like sections B form thecrests 21 b. In this manner, the corrugated fin body 1 a is provided. Inthe thus obtained corrugated fin body 1 a, the belt-like sections C formthe side walls 21 a and each of the fins 21 has a rectangular crosssection, or an angulated cross section.

The two opposing sets of the louvers 31 in each of the fins 21, or theset of the louvers 31 formed in one of the two adjacent side walls 21 aand the set of the louvers 31 formed in the other, are inclined inopposite directions with respect to the flow direction of the coolingmedium. Thus, as indicated by the arrows in FIG. 2, the cooling mediumat least rotates in the fins 21.

The heat sink 1 for power module according to the first embodiment formsa power module if an insulated circuit substrate 102 on which the powerdevices 101 such as semiconductor chips are mounted is arranged on thesurface of the heat sink 1. The power module may be used in an invertercircuit of a movable body such as a hybrid vehicle, which uses anelectric motor as one of its drive sources. The power module thusadjusts the power supplied to the electric motor or the like incorrespondence with the operating state of the movable body. The powermodule transmits intense heat generated by the power devices 101 to theheat sink 1 for power module through the insulated circuit substrate102. The heat is then dissipated by the cooling medium flowing in therefrigerant passage 1 d.

The heat sink 1 for power module according to the first embodimentincludes the corrugated fin body 1 a in the refrigerant passage 1 d. Thecorrugated fin body 1 a has the crests 21 b and the troughs 21 c, whichextend in the flow direction of the cooling medium, and the side walls21 a. Each of the side walls 21 a connects the corresponding one of thecrests 21 b with the adjacent one of the troughs 21 c. Each adjacentpair of the side walls 21 a and the associated one of the crests 21 b,which is located between the side walls 21 a, form the corresponding oneof the fins 21. Each of the side walls 21 a has the louvers 31, whichoperate to, at least, rotate the cooling medium flowing in theassociated fin 21. Thus, the heat sink 1 for power module facilitatesflow of the cooling medium between an area thermally close to the powerdevices 101 and an area thermally far from the power devices 101. Thissuppresses nonuniform distribution of the temperature of the coolingmedium in the refrigerant passage 1 d, allowing the cooling medium toeffectively perform cooling.

The heat dissipating efficiency is thus improved. As a result, the heatsink 1 for power module effectively transmits heat from the innersurfaces of the refrigerant passage 1 d and the surfaces of the fins 21to the cooling medium.

Accordingly, the heat sink 1 for power module according to the firstembodiment further improves the heat dissipating performance.

Further, since the louvers 31 operate to, at least, rotate the coolingmedium, erosion is prevented and durability is improved in the heat sink1 for power module.

Further, the two opposing sets of the louvers 31 in each of the fins 21of the heat sink 1 for power module are inclined in opposite directionswith respect to the flow direction of the cooling medium. The coolingmedium is thus guided by the louvers 31 as indicated by the arrows inFIG. 2. Specifically, when the cooling medium flows along one of theside walls 21 a of each fin 21, the cooling medium is guided by thelouvers 31 of the side wall 21 a. This sends the cooling medium to theother of the side walls 21 a past the crest 21 b or the trough 21 c. Thecooling medium is then further guided by the louvers 31 of the side wall21 a. In this manner, the cooling medium proceeds in the refrigerantpassage 1 d while rotating in each of the fins 21.

Each of the louvers 31 of the heat sink 1 for power module is formedthrough bending of the corresponding one of the portions of the sidewall 21 a defined by the cuts 31 a. This facilitates the formation ofthe louvers 31 and lowers the manufacturing costs. In this case, whenflowing in each fin 21, the cooling medium passes through the openingsin the side walls 21 a provided through formation of the louvers 31. Thecooling medium thus moves to the exterior of the fin 21 through the sidewalls 21 a. This further effectively suppresses the nonuniformdistribution of the temperature of the cooling medium.

Also, each of the waves formed by the corrugated fin body 1 a of theheat sink 1 for power module has a rectangular shape. That is, eachcrest 21 b and each trough 21 c have an angulated cross section. Thedistance between the side walls 21 a of each fin 21 is substantiallyconstant in the direction along the height (the up-and-down direction ofFIG. 2). This makes it easy for the louvers 31, which are located in thefins 21, to guide the cooling medium. Accordingly, the nonuniformtemperature distribution of the cooling medium is further effectivelysuppressed.

Second Embodiment

A second embodiment also corresponds to the first invention.

A heat sink 2 for power module corresponding to the second embodimentwill hereafter be explained, mainly with regard to the differencesbetween the heat sink 2 and the heat sink 1 for power module accordingto the first embodiment.

As shown in FIG. 5, a corrugated fin body 2 a is arranged in therefrigerant passage 1 d of the heat sink 2 for power module. Withreference to FIGS. 4 and 5, the corrugated fin body 2 a has crests 22 band troughs 22 c, which extend in the flow direction of the coolingmedium, and side walls 22 a. The crests 22 b and the troughs 22 c arealternately provided in a direction perpendicular to the flow directionof the cooling medium. Each of the side walls 22 a connects thecorresponding one of the crests 22 b with the adjacent one of thetroughs 22 c. Each adjacent pair of the side walls 22 a and theassociated one of the crests 22 b, which is located between the sidewalls 22 a, form a fin 22. Each of the crests 22 b and each of thetroughs 22 c of the corrugated fin body 2 a have roundly curved shapes.Specifically, each crest 22 b and each trough 22 c of the corrugated finbody 2 a have smoothly curved cross sections. This reduces the machiningcosts compared to the crests 21 b and the troughs 21 c according to thefirst embodiment, which have the angulated cross sections. Each of theside walls 22 a has two sets of louvers 32 located at mutually differentpositions in the direction along the height of the side wall 22 a (orthe direction along the height of each of the waves formed by thecorrugated fin body 2 a). The angles of the louvers 32 with respect tothe flow direction of the cooling medium or the sizes of the louvers 32may be varied between the lower set and the upper set. In this manner,the rotating flow of the cooling medium is easily regulated.

The heat sink 2 for power module according to the second embodiment,which is configured as above-described, has the advantages equivalent tothose of the heat sink 1 for power module according to the firstembodiment.

Third Embodiment

A third embodiment also corresponds to the first invention.

A heat sink 3 for power module corresponding to the third embodimentwill hereafter be explained, mainly with regard to the differencesbetween the heat sink 3 and the heat sink 1 for power module accordingto the first embodiment.

As shown in FIG. 7, a corrugated fin body 3 a is arranged in therefrigerant passage 1 d of the heat sink 3 for power module. Withreference to FIGS. 6 and 7, the corrugated fin body 3 a has crests 23 band troughs 23 c, which extend in the flow direction of the coolingmedium, and side walls 23 a. The crests 23 b and the troughs 23 c arealternately provided in a direction perpendicular to the flow directionof the cooling medium. Each of the side walls 23 a connects thecorresponding one of the crests 23 b with the adjacent one of thetroughs 23 c. Each adjacent pair of the side walls 23 a and theassociated one of the crests 23 b, which is located between the sidewalls 23 a, form a fin 23. Each of the crests 23 b and each of thetroughs 23 c of the corrugated fin body 3 a have roundly curved shapes.In other words, each crest 23 b and each trough 23 c of the corrugatedfin body 3 a have smoothly curved cross sections. Each of the side walls23 a has two sets of louvers 33 located at mutually different positionsin the direction along the height of the side wall 23 a (or thedirection along the height of each of the waves formed by the corrugatedfin body 3 a). The two opposing sets of the louvers 33 in each of thefins 23, or the set of the louvers 33 formed in one of the two adjacentside walls 23 a and the set of the louvers 33 formed in the other, areinclined in the same direction with respect to the flow direction of thecooling medium. Further, a number of through holes 33 b are provided ineach of the side walls 23 a at the two ends of the side wall 23 a in thedirection along the height of the side wall 23 a (or the two ends of theside wall 23 a in the direction along the height of each of the wavesformed by the corrugated fin body 3 a) and arranged in parallel with thelouvers 33.

In the heat sink 3 for power module, which is configured asabove-described, the cooling medium is guided by the louvers 33 asindicated by the arrows in FIG. 7. Specifically, the cooling mediumflows through the through holes 33 b and moves between the interior andthe exterior of the fins 23. In this manner, the cooling medium proceedsin the refrigerant passage 1 d while rotating. In other words, thecooling medium proceeds in the refrigerant passage 1 d while rotatingaround the side walls 23 a through the through holes 33 b. Thus, theheat sink 3 for power module according to the third embodiment has theadvantages equivalent to those of the heat sinks 1, 2 for power moduleaccording to the first and second embodiments.

Fourth Embodiment

A fourth embodiment also corresponds to the first invention.

A heat sink 4 for power module corresponding to the fourth embodimentwill hereafter be explained, mainly with regard to the differencesbetween the heat sink 4 and the heat sink 2 for power module accordingto the second embodiment.

As shown in FIG. 9, a corrugated fin body 4 a is arranged in therefrigerant passage 1 d of the heat sink 4 for power module. Withreference to FIGS. 8 and 9, the corrugated fin body 4 a has crests 24 band troughs 24 c, which extend in the flow direction of the coolingmedium, and side walls 24 a. The crests 24 b and the troughs 24 c arealternately provided in a direction perpendicular to the flow directionof the cooling medium. Each of the side walls 24 a connects thecorresponding one of the crests 24 b with the adjacent one of thetroughs 24 c. Each adjacent pair of the side walls 24 a and theassociated one of the crests 24 b or the associated one of the troughs24 c, which is located between the side walls 24 a, form a fin 24. Eachof the crests 24 b and each of the troughs 24 c of the corrugated finbody 4 a have roundly curved shapes. That is, each crest 24 b and eachtrough 24 c of the corrugated fin body 4 a have smoothly curved crosssections. Each of the side walls 24 a has upper louvers 34 a and lowerlouvers 34 b, which are located at mutually different positions in thedirection along the height of the side wall 24 a (or the direction alongthe height of each of the waves formed by the corrugated fin body 4 a).The upper louvers 34 a and the lower louvers 34 b are inclined in thesame direction with respect to the flow direction of the cooling medium.Further, each of the upper louvers 34 a and each of the lower louvers 34b are formed from portions of the side walls 24 a defined by cuts thatare bent in opposite directions.

In the heat sink 4 for power module according to the fourth embodiment,which is configured as above-described, the cooling medium is guided bythe louvers 34 a, 34 b, as indicated by the arrows in FIG. 9.Specifically, when flowing in each of the fins 24, the cooling medium isguided by the louvers 34 a, 34 b to rotate in the fin 24. Meanwhile, thecooling medium passes through the openings that are provided in the sidewalls 24 a through formation of the louvers 34 a, 34 b. In this manner,the cooling medium moves to the exterior of the fin 21 through the sidewalls 24 a. In other words, the cooling medium moves between theinterior and the exterior of the fin 24 through the holes defined in theside walls 24 a through the formation of the louvers 34 a, 34 b. In thismanner, the cooling medium proceeds in the refrigerant passage 1 d whilerotating. Thus, the heat sink 4 for power module according to the fourthembodiment has the advantages equivalent to those of the heat sinks 1 to3 for power module according to the first to third embodiments.

Fifth Embodiment

A fifth embodiment corresponds to the second invention.

Power devices 105 may be mounted on a surface of a heat sink 5 for powermodule according to the fifth embodiment, which is shown in FIG. 11. Theheat sink 5 has a refrigerant passage 5 d in which cooling medium fordissipating heat generated by the power devices 105 flows.

The refrigerant passage 5 d of the heat sink 5 for power module is aspace with a rectangular cross section surrounded by a surface 5 b, abackside 5 c, and side surfaces (not shown), which are provided atopposing sides. The cooling medium flows from the side closer to theviewer of FIG. 11 toward the side farther from the viewer of thedrawing.

A corrugated fin body 5 a is arranged in the refrigerant passage 5 d.The corrugated fin body 5 a has crests 25 b and troughs 25 c, whichextend in the flow direction of the cooling medium, and side walls 25 a.The crests 25 b and the troughs 25 c are alternately provided in adirection perpendicular to the flow direction of the cooling medium.Each of the side walls 25 a connects the corresponding one of the crests25 b with the adjacent one of the troughs 25 c. Each adjacent pair ofthe side walls 25 a and the associated one of the crests 25 b or theassociated one of the troughs 25 c, which is located between the sidewalls 25 a, form a fin 25. The outline of each crest 25 b and theoutline of each trough 25 c have a small bending radius butsubstantially define right angles. In other words, each of the wavesformed by the corrugated fin body 5 a has a rectangular shape. That is,each of the crests 25 b and each of the troughs 25 c have angulatedcross sections.

Referring to FIGS. 10 and 11, a guide 35 formed by an aluminum wire isprovided in each of the fins 25. Each of the guides 35 extends in theflow direction of the cooling medium while rotating along the inner sideof the fin 25. Thus, as indicated by the arrows in FIG. 11, the coolingmedium proceeds in the refrigerant passage 5 d while being rotated andstirred in the fin 25.

In the heat sink 5 for power module according to the fifth embodiment,which has the above-described structure, the cooling medium flowing ineach fin 25 is at least rotated and stirred by the associated guide 35.Thus, the cooling medium easily flows between an area thermally close tothe power devices 105 and an area thermally far from the power devices105. This suppresses nonuniform distribution of the temperature of thecooling medium in the refrigerant passage 5 d, allowing the coolingmedium to effectively perform cooling. The heat dissipating efficiencyis thus improved. As a result, the heat sink 5 for power module alsoeffectively transmits heat from the inner surfaces of the refrigerantpassage 5 d and the surfaces of the fins 25 to the cooling medium.

Accordingly, the heat sink 5 for power module according to the fifthembodiment further improves the heat dissipating performance.

Also, each of the waves formed by the corrugated fin body 5 a of theheat sink 5 for power module has a rectangular shape. The distancebetween the side walls 25 a of each fin 25 is substantially constant inthe direction along the height (the up-and-down direction of FIG. 11).This makes it easy for the guides 35, which are located in the fins 25,to guide the cooling medium.

Sixth Embodiment

A sixth embodiment also corresponds to the second invention.

As shown in FIGS. 12 and 13, in a heat sink 6 for power module accordingto the sixth embodiment, instead of the guide 35 of the heat sink 5 forpower module according to the fifth embodiment, a guide 36 having adifferent shape is provided in each of the fins 25. The other portionsof the sixth embodiment are configured identically to the correspondingportions of the heat sink 5 for power module according to the fifthembodiment. Description of these portions will thus be omitted.

Referring to FIG. 12, each of the guides 36 is formed through cuttingand bending of a thin metal plate. Each guide 36 has first slantedsurfaces 36 a that contact only one of the two associated side walls 25a and second slanted surface 36 b that contact only the other of theside walls 25 a. The first slanted surfaces 36 a and the second slantedsurfaces 36 b are alternately arranged in a repeated manner. Each of thefirst slanted surfaces 36 a and each of the second slanted surfaces 36 bare inclined in opposite directions with respect to the flow directionof the cooling medium. Thus, as indicated by the arrows in FIG. 13, thecooling medium proceeds in the refrigerant passage 5 d while beingstirred in each of the fins 25.

In the heat sink 6 for power module according to the sixth embodiment,which is configured as above described, the cooling medium flowing ineach fin 25 is stirred by the associated guide 36. Thus, the coolingmedium easily flows between an area thermally close to the power devices105 and an area thermally far from the power devices 105. Thissuppresses nonuniform distribution of the temperature of the coolingmedium in the refrigerant passage 5 d, allowing the cooling medium toeffectively perform cooling. The heat dissipating efficiency is thusimproved. As a result, the heat sink 6 for power module also effectivelytransmits heat from the inner surfaces of the refrigerant passage 5 dand the surfaces of the fins 25 to the cooling medium. Accordingly, theheat sink 6 for power module according to the sixth embodiment has theadvantages equivalent to those of the heat sink 5 for power moduleaccording to the fifth embodiment.

Seventh Embodiment

A seventh embodiment also corresponds to the second invention.

As shown in FIGS. 14, 15, and 16, in a heat sink 7 for power moduleaccording to the seventh embodiment, instead of the guide 36 of the heatsink 6 for power module according to the sixth embodiment, a guide 37having a different shape is provided in each of the fins 25. The otherportions of the seventh embodiment are configured identically to thecorresponding portions of the heat sink 6 for power module according tothe sixth embodiment. Description of these portions will thus beomitted.

Referring to FIGS. 14 and 15, each of the guides 37 is formed by guideforming members 37 c that are stacked. Each of the guide forming members37 c is formed through cutting and bending of a thin metal plate.

The height of each guide forming member 37 c is smaller than the heightof the guide 36 according to the sixth embodiment (FIG. 12). Each guideforming member 37 c has first slanted surfaces 37 a that contact onlyone of the two associated side walls 25 b and second slanted surface 37b that contact only the other of the side walls 25 a. The first slantedsurfaces 37 a and the second slanted surfaces 37 b are alternatelyarranged in a repeated manner. Each of the first slanted surfaces 37 aand each of the second slanted surfaces 37 b are inclined in oppositedirections with respect to the flow direction of the cooling medium.Thus, as indicated by the arrows in FIG. 16, the cooling medium proceedsin the refrigerant passage 5 d while being intensely stirred in each ofthe fins 25.

In the heat sink 7 for power module according to the seventh embodiment,which is configured as above described, the cooling medium flowing ineach fin 25 is stirred by the associated guide 37. Thus, the coolingmedium easily flows between an area thermally close to the power devices105 and an area thermally far from the power devices 105. Thissuppresses nonuniform distribution of the temperature of the coolingmedium in the refrigerant passage 5 d, allowing the cooling medium toeffectively perform cooling. The heat dissipating efficiency is thusimproved. As a result, the heat sink 7 for power module also effectivelytransmits heat from the inner surfaces of the refrigerant passage 5 dand the surfaces of the fins 25 to the cooling medium. Accordingly, theheat sink 7 for power module according to the seventh embodiment has theadvantages equivalent to those of the heat sinks 5, 6 for power moduleaccording to the fifth and sixth embodiments.

Eighth Embodiment

An eighth embodiment corresponds to the third invention.

A power device 108 may be mounted on a surface of a heat sink 8 forpower module according to the eighth embodiment, which is shown in FIG.18. The heat sink 8 has a refrigerant passage 8 d in which coolingmedium for dissipating heat generated by the power device 108 flows.

The refrigerant passage 8 d of the heat sink 8 for power module is aspace with a rectangular cross section surrounded by a surface 8 b, abackside 8 c, and side surfaces 8 e, which are provided at opposingsides. The cooling medium flows from the side closer to the viewer ofFIG. 18 toward the side farther from the viewer of the drawing.

A guide member 38 having first guide plates 81 a and second guide plates82 a is provided in the refrigerant passage 8 d.

With reference to FIG. 17, each of the first guide plates 81 a is formedby a corrugated fin body formed of aluminum, which includes crests 281 band troughs 281 c that are arranged alternately and side walls 281 aeach of which connects the corresponding one of the crests 281 b withthe adjacent one of the troughs 281 c. Each adjacent pair of the sidewalls 281 a and the associated one of the crests 281 b or the associatedone of the troughs 281 c, which is arranged between the side walls 281a, form a first fin 281. The first fin 281 guides the cooling medium ina direction inclined at a first angle (+α) with respect to the flowdirection of the cooling medium.

Like the first guide plates 81 a, each of the second guide plates 82 ais formed by a corrugated fin body formed of aluminum, which includescrests 282 b and troughs 282 c that are arranged alternately and sidewalls 282 a each of which connects the corresponding one of the crests282 b with the adjacent one of the troughs 282 c. Each adjacent pair ofthe side walls 282 a and the associated one of the crests 282 b or theassociated one of the troughs 282 c, which is arranged between the sidewalls 282 a, form a second fin 282. The second fin 282 guides thecooling medium in a direction inclined at a second angle (−α), which isdifferent from the first angle (+α), with respect to the flow directionof the cooling medium.

The guide member 38 is formed by the first guide plates 81 a and thesecond guide plates 82 a that are alternately stacked. In the guidemember 38, the first fins 281 and the second fins 282 are inclined withrespect to the flow direction of the cooling medium in such a mannerthat the first fins 281 cross the second fins 282.

In the heat sink 8 for power module according to the eighth embodiment,which has the above-described configuration, the cooling medium movesfrom the inner side of each first fin 281 of the first guide plate 81 ato the inner side of the corresponding second fin 282 of the secondguide plate 82 a at the side corresponding to the surface 8 b of therefrigerant passage 8 d, as indicated by the corresponding arrows inFIG. 18. The cooling medium then proceeds in the inner side of thesecond fin 282 in a direction inclined at the second angle (−α) withrespect to the flow direction of the cooling medium. Afterward, thecooling medium reaches the inner side of the corresponding first fin 281of the first guide plate 81 a at the side corresponding to the backside8 c of the refrigerant passage 8 d. The cooling medium then proceeds inthe inner side of the first fin 281 in a direction inclined at the firstangle (+α) with respect to the flow direction of the cooling medium.Further, the cooling medium flows from the inner side of each first fin281 of the first guide plate 81 a to the inner side of the correspondingsecond fin 282 of the second guide plate 82 a at a position in the firstfin 281. Likewise, the cooling medium flows from the inner side of eachsecond fin 282 of the second guide plate 82 a to the inner side of thecorresponding first fin 281 of the first guide plate 81 a at a positionin the second fin 282. Thus, the cooling medium easily flows between anarea thermally close to the power device 108 and an area thermally farfrom the power device 108. This suppresses nonuniform distribution ofthe temperature of the cooling medium in the refrigerant passage 8 d,allowing the cooling medium to effectively perform cooling. The heatdissipating efficiency is thus improved. As a result, the heat sink 8for power module effectively transmits heat from the inner surfaces ofthe refrigerant passage 8 d and the surfaces of the fins 281, 282 to thecooling medium.

Accordingly, the heat sink 8 for power module according to the eighthembodiment further improves the heat dissipating performance.

Ninth Embodiment

A ninth embodiment also corresponds to the third invention.

In a heat sink 9 for power module according to the ninth embodiment, apartition wall 39 is arranged between each first guide plate 81 a andthe adjacent second guide plate 82 a of the heat sink 8 for power moduleaccording to the eighth embodiment, as shown in FIGS. 19 and 20. Theother portions of the ninth embodiment are configured identically to thecorresponding portions of the heat sink 8 for power module. Thus,description of these portions will be omitted herein.

Each of the partition walls 39 is formed by a thin aluminum plate. Eachpartition wall 39 allows connection between the inner sides of theportions of the first fins 281 located at both ends of the partitionwall 39 in the direction perpendicular to the flow direction of thecooling medium and the inner sides of the portions of the second fins282 located at the same ends. Contrastingly, the partition wall 39prevents connection between the inner sides of the portions of the firstfins 281 located at the portions other than these ends and the innersides of the portions of the second fins 282 located at the sameportions.

In the heat sink 9 for power module according to the ninth embodiment,which has the above-described configuration, the cooling medium movesfrom the inner side of each first fin 281 of the first guide plate 81 ato the inner side of the corresponding second fin 282 of the secondguide plate 82 a at the side corresponding to the surface 8 b of therefrigerant passage 8 d, as indicated by the corresponding arrows inFIG. 20. The cooling medium then proceeds in the inner side of thesecond fin 282 in a direction inclined at the second angle (−α) withrespect to the flow direction of the cooling medium. Afterward, thecooling medium reaches the inner side of the corresponding first fin 281of the first guide plate 81 a at the side corresponding to the backside8 c of the refrigerant passage 8 d. The cooling medium then proceeds inthe inner side of the first fin 281 in a direction inclined at the firstangle (+α) with respect to the flow direction of the cooling medium. Onthe other hand, the partition walls 39 prevent the cooling medium fromflowing from the inner side of each first fin 281 of the first guideplate 81 a to the inner side of the corresponding second fin 282 of thesecond guide plate 82 a at a position in the first fin 281. Likewise,the partition walls 39 prevent the cooling medium from flowing from theinner side of each second fin 282 of the second guide plate 82 a to theinner side of the corresponding first fin 281 of the first guide plate81 a at a position in the second fin 282. The cooling medium is thuseffectively rotated and stirred in the heat sink 9 for power module.This makes it easy for the cooling medium to flow between an areathermally close to the power device 108 and an area thermally far fromthe power device 108. Nonuniform distribution of the temperature of thecooling medium in the refrigerant passage 8 d is thus suppressed.Accordingly, the cooling medium effectively performs cooling, thusimproving the heat dissipating efficiency. As a result, the heat sink 9for power module effectively transmits heat from the inner surfaces ofthe refrigerant passage 8 d and the surfaces of the fins 281, 282 to thecooling medium. Accordingly, the heat sink 9 for power module accordingto the ninth embodiment has the advantages equivalent to those of theheat sink 8 for power module according to the eighth embodiment.

Tenth Embodiment

A tenth embodiment corresponds to the fourth invention.

With reference to FIGS. 21, 22, and 23, a power device 110 may bemounted on a surface of a heat sink 10 for power module according to thetenth embodiment. The heat sink 10 has a refrigerant passage 10 d inwhich cooling medium for dissipating heat generated by the power device110 flows.

The refrigerant passage 10 d of the heat sink 10 for power module is aspace with a rectangular cross section surrounded by a surface 10 b, abackside 10 c, and side surfaces 10 e, which are provided at opposingsides. The cooling medium flows from the side closer to the viewer ofFIG. 21 toward the side farther from the viewer of the drawing.

A comb tooth member 310 formed of an aluminum extrusion is arranged inthe refrigerant passage 10 d. The comb tooth member 310 has a substrate310 a extending parallel with the surface on which the power device 110is arranged and upright walls 310 b projecting from the substrate 310 ain a direction crossing the surface on which the power device 110 isprovided. Each of the upright walls 310 b extends in the flow directionof the cooling medium in the refrigerant passage 10 d.

As shown in FIGS. 22 and 23, projections 310 d and recesses 310 c, whichserve as guide portions, are provided on the side surfaces of each ofthe upright walls 310 b and spaced at a predetermined interval. Theprojections 310 d and the recesses 310 c are provided through cutting ofthe side surfaces of each upright wall 310 b using a rotary blade 310 e.The projections 310 d and the recesses 310 c of each upright wall 310 boperate to stir the cooling medium flowing between the upright wall 310b and the adjacent one of the upright walls 310 b. To provide theprojections 310 d and the recesses 310 c in the upright wall 310 b, asillustrated in FIG. 23, the rotary blade 310 e is applied to eachadjacent pair of the upright walls 310 b diagonally with respect to theextending direction of each upright wall 310 b, in such a manner thatthe rotary blade 310 e forms the projections 310 d and the recesses 310c by simultaneously cutting the two opposing side surfaces of theupright walls 310 b. Thus, the projections 310 d and the recesses 310 c,which are arranged on the two opposing side surfaces of the adjacentupright walls 310 b, are inclined in opposite directions with respect tothe flow direction of the cooling medium.

In the heat sink 10 for power module according to the tenth embodiment,the cooling medium is stirred by the guide portions formed by theprojections 310 d and the recesses 310 c when flowing between theupright walls 310 b of the comb tooth member 310. This makes it easy forthe cooling medium to flow between an area thermally close to the powerdevice 110 and an area thermally far from the power device 110.Nonuniform distribution of the temperature of the cooling medium in therefrigerant passage 10 d is thus suppressed and the cooling mediumeffectively performs cooling. This improves the heat dissipatingefficiency. As a result, the heat sink 10 for power module effectivelytransmits heat from the inner surfaces of the refrigerant passage 10 dand the surfaces of the upright walls 310 b to the cooling medium.

Accordingly, the heat sink 10 for power module according to the tenthembodiment further improves the heat dissipating performance.

Further, in the heat sink 10 for power module, the projections 310 d andthe recesses 310 c, which are arranged at the two opposing side surfacesof each adjacent pair of the upright walls 310, are inclined in theopposite directions with respect to the flow direction of the coolingmedium. Thus, the cooling medium easily moves between the opposing twoside surfaces of the adjacent upright walls 310 while being guided bythe projections 310 d and the recesses 310 c.

Although the surface 10 b and the comb tooth member 310 are provided asseparate bodies in the heat sink 10 for power module according to thetenth embodiment, the surface 10 b and the comb tooth member 310 may beformed integrally with each other.

Eleventh Embodiment

An eleventh embodiment also corresponds to the fourth invention.

In a heat sink 11 for power module according to the eleventh embodiment,a comb tooth member 311 shown in FIGS. 24 and 25 is provided in therefrigerant passage 10 d, instead of the comb tooth member 310 of theheat sink 10 for power module according to the tenth embodiment. Theother portions of the eleventh embodiment are configured identically tothe corresponding portions of the heat sink 10 for power moduleaccording to the tenth embodiment. Description of these portions willthus be omitted herein.

The comb tooth member 311 is formed of an aluminum extrusion and has asubstrate 311 a extending parallel with the surface on which the powerdevice 110 is arranged and upright walls 311 b projecting from thesubstrate 311 a in a direction crossing the surface on which the powerdevice 110 is provided. Each of the upright walls 311 b extends in theflow direction of the cooling medium in the refrigerant passage 10 d.

As shown in FIG. 26, groove-like recesses 311 c, each of which has arectangular cross section and serves as a guide portion, are provided onthe side surfaces of each of the upright walls 311 b and spaced at apredetermined interval. The recesses 311 c are provided throughbroaching of the side surfaces of each upright wall 311 b using abroaching tool 311 e. The recesses 311 c of each upright wall 311 boperate to stir the cooling medium flowing between the upright wall 311b and the adjacent one of the upright walls 311 b. Referring to FIG. 25,the recesses 311 c arranged on the two opposing side surfaces of eachadjacent pair of the upright walls 311 b are inclined in oppositedirections with respect to the flow direction of the cooling medium.

Like the heat sink 10 for power module according to the tenthembodiment, in the heat sink 11 for power module according to theeleventh embodiment, which is configured as above-described, the coolingmedium is stirred by the guide portions defined by the recesses 311 cwhen flowing between the upright walls 311 b of the comb tooth member311. This makes it easy for the cooling medium to flow between an areathermally close to the power device 110 and an area thermally far fromthe power device 110. Nonuniform distribution of the temperature of thecooling medium in the refrigerant passage 10 d is thus suppressed andthe cooling medium effectively performs cooling. This improves the heatdissipating efficiency. As a result, the heat sink 11 for power moduleeffectively transmits heat from the inner surfaces of the refrigerantpassage 10 d and the surfaces of the upright walls 311 b to the coolingmedium. Accordingly, the heat sink 11 for power module according to theeleventh embodiment has the advantages equivalent to those of the heatsink 10 for power module according to the tenth embodiment.

Twelfth Embodiment

A twelfth embodiment also corresponds to the fourth invention.

In a heat sink 12 for power module according to the twelfth embodiment,a comb tooth member 312 shown in FIGS. 27 and 28 is provided in therefrigerant passage 10 d, instead of the comb tooth member 310 of theheat sink 10 for power module according to the tenth embodiment. Theother portions of the twelfth embodiment are configured identically tothe corresponding portions of the heat sink 10 for power moduleaccording to the tenth embodiment. Description of these portions willthus be omitted herein.

The comb tooth member 312 is formed of an aluminum extrusion and has asubstrate 312 a extending parallel with the surface on which the powerdevice 110 is arranged and upright walls 312 b projecting from thesubstrate 312 a in a direction crossing the surface on which the powerdevice 110 is provided. Each of the upright walls 312 b extends in theflow direction of the cooling medium in the refrigerant passage 10 d.

As shown in FIG. 29, groove-like recesses 312 c, each of which has asemi-circular cross section and serves as a guide portion, are providedon the side surfaces of each of the upright walls 312 b and spaced at apredetermined interval. The recesses 312 c are provided through cuttingof the side surfaces of each upright wall 312 b using a drill blade (notshown). The recesses 312 c of each upright wall 312 b operate to stirthe cooling medium flowing between the upright wall 312 b and theadjacent one of the upright walls 312 b.

Referring to FIG. 28, the recesses 312 c arranged on the two opposingside surfaces of each adjacent pair of the upright walls 312 b areinclined in opposite directions with respect to the flow direction ofthe cooling medium.

In the heat sink 12 for power module according to the twelfthembodiment, the cooling medium is stirred by the guide portions definedby the recesses 312 c when flowing between the upright walls 312 b ofthe comb tooth member 312. This makes it easy for the cooling medium toflow between an area thermally close to the power device 110 and an areathermally far from the power device 110. Nonuniform distribution of thetemperature of the cooling medium in the refrigerant passage 10 d isthus suppressed. Accordingly, the cooling medium effectively performscooling and improves the heat dissipating efficiency. As a result, theheat sink 12 for power module has the advantages equivalent to those ofthe heat sinks 10, 11 for power module according to the tenth andeleventh embodiments.

Thirteenth Embodiment

A thirteenth embodiment also corresponds to the fourth invention.

In a heat sink for power module according to the thirteenth embodiment,through holes 313 c each serving as a guide portion illustrated in FIG.30 are provided in the comb tooth member 312, instead of the recesses312 c of the comb tooth member 312 of the heat sink 12 for power moduleaccording to the twelfth embodiment. The other portions of thethirteenth embodiment are configured identically to the correspondingportions of the heat sink 12 for power module according to the tenthembodiment. Description of these portions will thus be omitted herein.

Referring to FIG. 30, the through holes 313 c, which are defined in eachof the upright walls 312 b of the comb tooth member 312, are inclined atpredetermined angles with respect to a direction perpendicular to eachside surface of the upright wall 312 b (or, the direction along thethickness of the upright wall 312 b). Thus, while flowing in therefrigerant passage 10 d, the cooling medium moves from the vicinity ofone of the upright walls 312 b to the vicinity of another upright wall312 b through the through holes 313 c. In other words, the coolingmedium flows between two areas in the refrigerant passage 10 d that areseparated from each other by each upright wall 312 b through the throughholes 313 c. The through holes 313 c of each upright wall 312 b thusoperate to stir the cooling medium flowing between the upright wall 312b and the adjacent one of the upright walls 312 b.

In the heat sink for power module according to the thirteenthembodiment, the cooling medium is stirred by the guide portions definedby the through holes 313 c when flowing between each adjacent pair ofthe upright walls 312 b of the comb tooth member 312. Accordingly, theheat sink for power module according to the thirteenth embodiment hasthe advantages equivalent to those of the heat sinks 10 to 12 for powermodule according to the tenth to twelfth embodiments.

Fourteenth Embodiment

A fourteenth embodiment corresponds to the fifth invention.

As shown in FIGS. 31, 32, and 33, a heat sink 14 for power moduleaccording to the fourteenth embodiment includes a laminated body havingfirst passage plates 314 a, a second passage plate 314 b, and a thirdpassage plate 314 c that are joined together. The first to third passageplates 314 a, 314 b, 314 c are each formed of aluminum alloy. The thirdpassage plate 314 c, which is the uppermost layer, is simply a flatplate. The second passage plate 314 b, or the lowermost layer, and eachof the first passage plates 314 a, which forms the intermediate layer,have a joint surface 214 a in which parallel grooves 214 b are defined.Each of the grooves 214 b functions as a refrigerant passage 14 d inwhich cooling medium for dissipating heat generated by a power device114 (see FIG. 33) flows. First through holes 214 c and second throughholes 214 d, which serve as guide portions operating to stir the coolingmedium flowing in the corresponding one of the grooves 241 b, aredefined in each of the first passage plates 314 a in correspondence withthe grooves 214 d.

With reference to FIGS. 31 to 33, the four side surfaces defining eachof the first through holes 214 c include two side surfaces 214 e, 214 f,which are adjacently arranged in the flow direction of the coolingmedium. The four side surfaces defining each of the second through holes214 d include two side surfaces 214 g, 214 h, which are adjacentlyarranged in the flow direction of the cooling medium. The side surfaces214 e, 214 f and the side surfaces 214 g, 214 h are inclined in oppositedirections with respect to the flow direction of the cooling medium.

The joint surfaces 214 a of the first to third passage plates 314 a, 314b, 314 c are joined together to close the grooves 214 b of the firstpassage plates 314 a and the second passage plate 314 b. In this manner,the refrigerant passages 14 d are defined. The joint surfaces 214 a ofthe first to third passage plates 314 a, 314 b, 314 c are joinedtogether through, for example, brazing.

In the heat sink 14 for power module according to the fourteenthembodiment, the cooling medium flowing in the refrigerant passages 14 ddefined by the grooves 214 b is stirred through the first and secondthrough holes 214 c, 214 d. This makes it easy for the cooling medium toflow between an area thermally close to the power device 114 and an areathermally far from the power device 114. Nonuniform distribution of thetemperature of the cooling medium in each of the refrigerant passages 14d is thus suppressed and the cooling medium effectively performscooling. The heat dissipating efficiency is thus improved. As a result,the heat sink 14 for power module effectively transmits heat from theinner surfaces of the refrigerant passages 14 d and the surfaces of thefirst to third passage plates 314 a, 314 b, 314 c to the cooling medium.

Accordingly, the heat sink 14 for power module according to thefourteenth embodiment further improves the heat dissipating performance.

Further, in the heat sink 14 for power module according to thefourteenth embodiment, the two side surfaces 214 e, 214 f of each firstthrough hole 214 c and the two side surfaces 214 g, 214 h of each secondthrough hole 214 d are inclined in the opposite directions with respectto the flow direction of the cooling medium. This allows the coolingmedium to flow among the different grooves 214 b while being guided bythe first through holes 214 c and the second through holes 214 d. Morespecifically, each first through hole 214 c guides the cooling mediumfrom one of each adjacent pair of the refrigerant passages 14 d to theother. Each second through hole 214 d guides the cooling medium in theopposite direction, or from the latter refrigerant passage 14 d to theformer refrigerant passage 14 d. This makes it easy for the heat sink 14for power module to rotate the cooling medium, which further reliablyimproves the heat dissipating performance.

Fifteenth Embodiment

A fifteenth embodiment also corresponds to the fifth invention.

A heat sink 15 for power module according to the fifteenth embodimentwill now be explained mainly with regard to the differences between theheat sink 15 and the heat sink 14 for power module according to thefourteenth embodiment.

As shown in FIGS. 34, 35, and 36, the heat sink 15 for power moduleaccording to the fifteenth embodiment includes a laminated body havingfirst passage plates 315 a, a second passage plate 315 b, and a thirdpassage plate 315 c that are joined together. The first to third passageplates 315 a, 315 b, 315 c are each formed of aluminum alloy. The thirdpassage plate 315 c, which is the uppermost layer, is simply a flatplate. The second passage plate 315 b, or the lowermost layer, and eachof the first passage plates 315 a, which forms an intermediate layer,have a joint surface 215 a in which parallel grooves 215 b are defined.Each of the grooves 215 b functions as a refrigerant passage 15 d inwhich cooling medium for dissipating heat generated by the power device114 flows. First through holes 215 c and second through holes 215 d,which serve as guide portions operating to stir the cooling mediumflowing in the corresponding one of the grooves 215 b, are defined ineach of the first passage plates 315 a in correspondence with thegrooves 215 d.

First projections 215 e project from each of the first passage plates315 a in correspondence with the first through holes 215 c. Further,second projections 215 g project from each first passage plate 315 a incorrespondence with the second through holes 215 d. Each of the firstprojections 215 e and each of the second projections 215 g are definedthrough bending of corresponding portions of the first passage plate 315a each of which is defined by a cut. In this manner, the firstprojections 215 e and the second projections 215 g project into thecorresponding grooves 215 b. The first projections 215 e and the secondprojections 215 g are inclined in opposite directions with respect tothe flow direction of the cooling medium.

The joint surfaces 215 a of the first, the second, and the third passageplates 315 a, 315 b, 315 c are joined together to close the grooves 215b of the first passage plates 315 a and the second passage plate 315 b,thus defining refrigerant passages 15 d.

In the heat sink 15 for power module according to the fifteenthembodiment, which is configured as above-described, the cooling mediumflowing in the refrigerant passages 15 d defined by the grooves 215 b isstirred by not only the first and second through holes 215 c, 215 d butalso the first and second projections 215 e, 215 g. The heat sink 15 forpower module according to the fifteenth embodiment further reliablybrings about the advantages equivalent to those of the heat sink 14 forpower module according to the fourteenth embodiment.

Sixteenth Embodiment

A sixteenth embodiment also corresponds to the fifth invention.

A heat sink 16 for power module according to the sixteenth embodimentwill now be explained mainly with regard to the differences between theheat sink 16 and the heat sink 14 for power module according to thefifteenth embodiment.

As shown in FIGS. 37, 38, and 39, the heat sink 16 for power moduleaccording to the sixteenth embodiment includes a laminated body havingfirst passage plates 316 a, a second passage plate 316 b, and a thirdpassage plate 316 c that are joined together. The first to third passageplates 316 a, 316 b, 316 c are each formed of aluminum alloy. The thirdpassage plate 316 c, which is the uppermost layer, is simply a flatplate. The second passage plate 316 b, or the lowermost layer, and eachof the first passage plates 316 a, which forms an intermediate layer,have a joint surface 216 a in which parallel grooves 216 b are defined.Each of the grooves 216 b functions as a refrigerant passage 16 d inwhich cooling medium for dissipating heat generated by the power device114 flows.

In each of the grooves 216 b, corrugated fin bodies 216 j are alignedalong the flow direction of the cooling medium. Each of the corrugatedfin bodies 216 j is formed through bending of a thin aluminum plate.

First through holes 216 c and second through holes 216 d, which formguide portions that operate to stir the cooling medium flowing in thecorresponding grooves 216 b, are defined in each of the first passageplates 316 a in correspondence with the grooves 216 b. Also, each of thefirst through holes 216 c and each of the second through holes 216 d areprovided between the corresponding adjacent pair of the corrugated finbodies 216 j.

First projections 216 e project from each of the first passage plates316 a in correspondence with the first through holes 216 c. Further,second projections 216 g project from each first passage plate 316 a incorrespondence with the second through holes 216 d. Each of the firstprojections 216 e and each of the second projections 216 g are definedthrough bending of corresponding portions of the corresponding firstpassage plate 316 a each of which is defined by a cut. In this manner,the first projections 216 e and the second projections 216 g projectinto the corresponding grooves 216 b. The first projections 216 e andthe second projections 216 g are inclined in opposite directions withrespect to the flow direction of the cooling medium.

In the heat sink 16 for power module according to the sixteenthembodiment, which is configured as above-described, the corrugated finbodies 216 j greatly increase the contact area with respect to thecooling medium. This increases the amount of the heat transmitted to thecooling medium flowing in the refrigerant passages 16 d. Further, thecooling medium proceeds along the corrugated fin bodies 216 j in therefrigerant passages 16 d while being stirred by not only the first andsecond through holes 216 c, 216 d but also the first and secondprojections 216 e, 216 g. As a result, the heat sink 16 for power moduleaccording to the sixteenth embodiment further reliably brings about theadvantages equivalent to those of the heat sinks 14, 15 for power moduleaccording to the fourteenth and fifteenth embodiments.

Seventeenth Embodiment

A seventeenth embodiment corresponds to the sixth invention.

With reference to FIGS. 40, 41, 42, and 43, power devices 95 may bemounted on a surface of a heat sink 17 for power module according to theseventeenth embodiment. The heat sink 17 has a refrigerant passage 17 din which cooling medium for dissipating heat generated by the powerdevices 95 flows. A supply pipe 96, which supplies the cooling medium,is connected to an end of the heat sink 17 for power module.

The refrigerant passage 17 d of the heat sink 17 for power module is aspace with a rectangular cross section surrounded by a surface 17 b, abackside 17 c, and side surfaces 17 e, which are provided at opposingsides. The cooling medium, which is supplied from the supply pipe 96 tothe refrigerant passage 17 d, flows in the refrigerant passage 17 d fromthe left side toward the right side, as viewed in FIGS. 40, 41, and 43.

Comb tooth members 317 are arranged in the refrigerant passage 17 d andaligned along the flow direction of the cooling medium. Each of the combtooth members 317 is formed of an aluminum extrusion. Each comb toothmember 317 has a substrate 317 a extending parallel with the surface onwhich the power devices 95 are arranged and upright walls 317 bprojecting from the substrate 317 a in a direction crossing the surfaceon which the power devices 95 are provided. Each of the upright walls317 b extends in the flow direction of the cooling medium in therefrigerant passage 17 d.

An exchange device 217 is provided between each adjacent pair of thecomb tooth members 317. Referring to FIGS. 40 and 43, a first passage217 a and a second passage 217 b are defined in each of the exchangedevices 217. The first passages 217 a and the second passages 217 b arearranged alternately in the direction along the width of the refrigerantpassage 17 d (the direction perpendicular to the flow direction of thecooling medium). Each of the first passages 217 a operates to move thecooling medium from the side corresponding to the surface to the sidecorresponding to the backside in the refrigerant passage 17. In otherwords, each first passage 217 a operates to move the cooling medium froman area in the refrigerant passage 17 d close to the surface on whichthe power devices 95 are located to an area in the refrigerant passage17 d far from this surface. Each of the second passages 217 b operatesto move the cooling medium from the side corresponding to the backsideto the side corresponding to the surface in the refrigerant passage 17.That is, each second passage 217 b operates to move the cooling mediumfrom the area in the refrigerant passage 17 d far from the surface onwhich the power devices 95 are mounted to the area in the refrigerantpassage 17 d close to this surface.

The exchange devices 217 are manufactured using the followingmanufacturing method.

Specifically, as illustrated in FIGS. 44( a), 44(b), and 44(c), firstplates 418 a formed of aluminum alloy in which the first passages 217 aare defined and second plates 418 b formed of aluminum alloy in whichthe second passages 217 b are defined are alternately laminated in thedirection along the width of the refrigerant passage 17 d to form alaminated body 418 c. Next, as illustrated in FIGS. 45( a) and 45(b),the laminated body 418 c is cut to provide the exchange devices 217. Themanufacturing method decreases the costs for manufacturing the heat sink17 for power module according to the seventeenth embodiment.

The heat sink 17 for power module according to the seventeenthembodiment also forms a power module when the power devices 95 aremounted on the surface of the heat sink 17.

In the heat sink 17 for power module according to the seventeenthembodiment, the exchange devices 217 in the refrigerant passage 17 doperate to move the cooling medium from the side corresponding to thesurface to the side corresponding to the backside and from the surfaceto the side corresponding to the backside to the side corresponding tothe surface. Thus, the cooling medium easily flows between an areathermally close to the power devices 95 and an area thermally far fromthe power devices 95. This suppresses nonuniform distribution of thetemperature of the cooling medium in the refrigerant passage 17 d,allowing the cooling medium to effectively perform cooling. The heatdissipating efficiency is thus improved. As a result, the heat sink 17for power module effectively transmits heat from the inner surfaces ofthe refrigerant passage 17 d to the cooling medium.

Accordingly, the heat sink 17 for power module according to theseventeenth embodiment further improves the heat dissipatingperformance.

Eighteenth Embodiment

An eighteenth embodiment also corresponds to the sixth invention.

In a heat sink for power module according to the eighteenth embodiment,exchange devices 418 illustrated in FIG. 46 are provided in therefrigerant passage 17 d, instead of the exchange devices 217 of theheat sink 17 for power module according to the seventeenth embodiment.The other portions of the eighteenth embodiment are configuredidentically to the corresponding portions of the heat sink 17 for powermodule according to the seventeenth embodiment. Description of theseportions will thus be omitted herein.

Referring to FIG. 46, to form the exchange devices 218, cuts areprovided in the opposing long sides of a thin metal plate having anelongated shape. Then, each adjacent pairs of cut pieces 218 a of one ofthe long sides are bent to be inclined at an inclination angle inopposite directions. Afterwards, cut pieces 218 b of the other long sideare bent to be inclined at the inclination angle in opposite directionsto those of the opposing cut pieces 218 a. The manufacturing methoddecreases the costs for manufacturing the heat sink for power moduleaccording to the eighteenth embodiment.

In the heat sink for power module having such exchange devices 218according to the eighteenth embodiment, the exchange devices 218 operateto move the cooling medium from the side corresponding to the surface tothe side corresponding to the backside and from the side correspondingto the backside to the side corresponding to the surface. Thus, the heatsink for power module according to the eighteenth embodiment has theadvantages equivalent to those of the heat sink 17 for power moduleaccording to the seventeenth embodiment.

Nineteenth Embodiment

A nineteenth embodiment corresponds to the sixth invention.

In a heat sink for power module according to the nineteenth embodiment,exchange devices 219 illustrated in FIG. 47 are provided in therefrigerant passage 17 d, instead of the exchange devices 217 of theheat sink 17 for power module according to the seventeenth embodiment.The other portions of the nineteenth embodiment are configuredidentically to the corresponding portions of the heat sink 17 for powermodule according to the seventeenth embodiment. Description of theseportions will thus be omitted herein.

Referring to FIG. 47, first projections 219 a and second projections 219b, which are inclined in opposite directions, are formed alternately ineach of the exchange devices 219. Each exchange device 219 is formedthrough pressing of an belt-like metal plate. The manufacturing methodreduces the costs for manufacturing the heat sink for power moduleaccording to the eighteenth embodiment.

In the heat sink for power module having such exchange devices 219according to the nineteenth embodiment, the exchange devices 219 operateto move the cooling medium from the side corresponding to the surface tothe side corresponding to the backside and the side corresponding to thebackside to the side corresponding to the surface. Thus, the heat sinkfor power module according to the nineteenth embodiment has theadvantages equivalent to those of the heat sink 17 for power moduleaccording to the seventeenth embodiment.

Although the first to nineteenth embodiments of the present inventionhave been described so far, the invention is not restricted to theseembodiments and may be modified as desired without departing from thescope of the invention.

1. A power module comprising: a power device; and a heat sink to whichheat generated by the power device is transmitted, the heat sinkincluding: a refrigerant passage in which a cooling medium thatdissipates the heat generated by the power device flows, the refrigerantpassage is defined by a surface and a backside, and the power device isdisposed in proximity to said surface; and a corrugated fin bodyarranged in the refrigerant passage, wherein the corrugated fin body hascrests and troughs that extend in a flow direction of the cooling mediumand side walls each of which connects the corresponding one of thecrests with the adjacent one of the troughs, wherein each adjacent pairof the side walls and the corresponding one of the crests or thecorresponding one of the troughs arranged between the adjacent sidewalls form a fin, and wherein a guide that extends in the flow directionof the cooling medium and operates to stir the cooling medium isarranged in each of the fins.
 2. The power module according to claim 1,wherein a wave formed by the corrugated fin body has a rectangularshape.
 3. A power module comprising: a power device; and a heat sink towhich heat generated by the power device is transmitted, the heat sinkincluding: a refrigerant passage in which a cooling medium thatdissipates the heat generated by the power device flows, the refrigerantpassage is defined by a surface and a backside, and the power device isdisposed in proximity to said surface; and a guide member arranged inthe refrigerant passage, wherein the guide member has a first guideplate and a second guide plate, wherein the first guide plate is formedby a corrugated fin body including crests and troughs that arealternately arranged, and side walls each of which connects thecorresponding one of the crests with the adjacent one of the troughs,wherein each adjacent pair of the side walls and the corresponding oneof the crests or the corresponding one of the troughs arranged betweenthe adjacent side walls form a first fin, the first fin operating toguide the cooling medium in a direction inclined at a first angle withrespect to a flow direction of the cooling medium, and wherein thesecond guide plate is formed by a corrugated fin body including crestsand troughs that are alternately arranged, and side walls each of whichconnects the corresponding one of the crests with the adjacent one ofthe troughs, wherein each adjacent pair of the side walls and thecorresponding one of the crests or the corresponding one of the troughsarranged between the adjacent side walls form a second fin, the secondfin operating to guide the cooling medium in a direction inclined at asecond angle, which is different from the first angle, with respect tothe flow direction of the cooling medium.
 4. The power module accordingto claim 3, wherein a partition wall is arranged between the first guideplate and the second guide plate, the partition wall allowing connectionbetween an inner side of a portion of the first fin and an inner side ofa portion of the second fin that are located at each of two ends of thepartition wall in a direction perpendicular to the flow direction of thecooling medium, and prohibiting connection between an inner side of aportion of the first fin and an inner side of a portion of the secondfin that are arranged at the positions other than the ends.
 5. The powermodule according to claim 3, wherein a wave formed by the first guideplate and a wave formed by the second guide plate each have arectangular shape.
 6. A power module comprising: a power device; and aheat sink to which heat generated by the power device is transmitted,the heat sink including: a refrigerant passage in which a cooling mediumthat dissipates the heat generated by the power device flows; and a combtooth member arranged in the refrigerant passage, wherein the comb toothmember has a substrate extending parallel with the surface on which thepower device is arranged and a plurality of upright walls that projectfrom the substrate in a direction crossing the surface on which thepower device is arranged, each of the upright walls extending along aflow direction of the cooling medium in the refrigerant passage, whereineach upright wall has a guide portion that operates to stir the coolingmedium flowing between the upright wall and the adjacent one of theupright walls.
 7. The power module according to claim 6, wherein theguide portion provided in one of two opposing surfaces of each adjacentpair of the upright walls and the guide portion provided in the other ofthe opposing surfaces are inclined in opposite directions with respectto the flow direction of the cooling medium.
 8. The power moduleaccording to claim 6, wherein each of the guide portions includes aprojection projecting from the corresponding one of the upright walls.9. The power module according to claim 6, wherein each of the guideportions includes a recess formed in the corresponding one of theupright walls.
 10. The power module according to claim 6, wherein eachof the guide portions includes a through hole formed in thecorresponding one of the upright walls.
 11. A power module comprising: apower device; and a heat sink to which heat generated by the powerdevice is transmitted, the heat sink including: a laminated bodyincluding a plurality of passage plates that are joined together; and aplurality of parallel grooves that are arranged between each adjacentpair of the passage plates, wherein each of the grooves functions as arefrigerant passage in which a cooling medium that dissipates the heatgenerated by the power device flows, and wherein each of the passageplates includes a guide portion operating to stir the cooling mediumflowing in the corresponding groove.
 12. The power module according toclaim 11, wherein the guide portions include a first set of guideportions and a second set of guide portions that are provided incorrespondence with each of the grooves, and wherein the first set ofguide portions and the second set of guide portions are inclined inopposite directions with respect to a flow direction of the coolingmedium.
 13. The power module according to claim 11, wherein each of theguide portions includes a projection projecting from the correspondingone of the passage plates.
 14. The power module according to claim 11,wherein each of the guide portions includes a recess formed in thecorresponding one of the passage plates.
 15. The power module accordingto claim 11, wherein each of the guide portions includes a through holeformed in the corresponding one of the passage plates.
 16. A powermodule comprising: a power device; and a heat sink to which heatgenerated by the power device is transmitted, the heat sink including: arefrigerant passage in which a cooling medium that dissipates the heatgenerated by the power device flows, the refrigerant passage is definedby a surface and a backside, and the power device is disposed inproximity to said surface; and an exchange device arranged in therefrigerant passage, wherein the exchange device moves the coolingmedium from an area of the refrigerant passage close to the surface onwhich the power device is provided to an area of the refrigerant passagefar from the surface on which the power device is provided, and from thearea of the refrigerant passage far from the surface on which the powerdevice is provided to the area of the refrigerant passage close to thesurface on which the power device is provided.
 17. The power moduleaccording to claim 16, wherein the exchange device has a first passageand a second passage, wherein the first passage moves the cooling mediumfrom the area of the refrigerant passage close to the surface on whichthe power device is provided to the area of the refrigerant passage farfrom the surface on which the power device is provided, and the secondpassage moves the cooling medium from the area of the refrigerantpassage far from the surface on which the power device is provided tothe area of the refrigerant passage close to the surface on which thepower device is provided, and wherein the first passage and the secondpassage are arranged alternately in a direction along a width of therefrigerant passage.
 18. The power module according to claim 17, whereinin the exchange device, a first plate in which the first passage isprovided and a second plate in which the second passage is provided arelaminated in the direction along the width of the refrigerant passage.